The goals of these studies are to investigate the natural history of central nervous system injury, to investigate the cellular response of the CNS to injury, and methods of treating the deficits produced by injury. The program involves a multi-disciplinary group of neurosurgeons, neurologists, neurophysiologists, morphologists, neurochemists, biomedical engineers, neuropsychologists and biostatisticians. Research is directed to understanding mechanisms and ultimately to improving outcome in the successive stages of treatment after injury: 1. transport to the hospital and emergency care; 2. operative treatment and monitoring in the intensive care unit; 3. outcome and rehabilitation. A computerized data recording system has been developed to record, retrieve and correlate neurological, neurophysiological and laboratory data from the clinical projects. The natural history of head injury is being studied. The severity of injury is characterized by means of neurological grading and neurophysiological studies and is being related to neuropsychological and neurological outcome. Electrophysiological monitoring of the severely injured patient is being carried out. The excitability of the cortex is tested with the direct cortical response and with evoked potential techniques, and related to measurements of brain swelling and circulatory changes. The mechanisms of development of subendocardial hemorrhages and cardiac arrhythmias after head injury are under study. The catabolic state after head injury with prolonged coma is under study, as are ways of improving the nutritional status of patients with peripheral amino acid infusions. Neuropathological studies of patterns of brain damage after fatal injury are being carried out. Neurochemical studies of neurotransmitter levels in the CSF after injury are being performed. Experimental studies are being carried out that are correlated with the clinical studies. Investigations are being made of the reactions of neurons, glia and capilliaries after injury. Mechanisms of regeneration in the CNS are being studied. The organization of the innervation of the bladder is being studied in relation to methods of improving bladder function after spinal injury, and neural prostheses in the improvement of bladder and motor paresis after injury are being studied.